Extension lamp-fixture



To all whom it may concern NITED STATES DEXTER W. PARKER, OF

MERIDEN, CONNECTICUT.

EXTENSION LAM P-FIXTURE.

SPECIFICATION forming part of Letters Patent No. 269,105, dated December12, 1882.

Application filed November 8, 1882. (No model.)

Be it known that I, DEXTER W. PARKER, a

citizen of the United States, residing at Meriden, in the county of NewHaven and State of Connecticut, have invented certain new and usefulImprovements in Extension Lamp-Fixtures; and I do hereby declare thefollowing to be a full, clear, and exact description of theinvention,such as will enable others skilled in the art to. which itappertains to make and use the sa'me, reference being had to theaccompanying drawings, and to letters or figures of refercnce'markedthereon, which form a partj of this specification. This inventionrelates to clamping devices for securing the tubes of an extensionlampiixture in any position ordegree of extension desired; and itconsists principally in a shoe 1 or clamping-piece arranged to bearagainst the inner tube or rod, in combination with a s1iding wedge,which operates between a tubularattachmentof the outer tube and saidshoe to crowd'the latteragainst said inner tube, for the purpose stated.

the wedge to make such clamping action auto- Italso consists in thecombinatiomwith the foregoing devices, ot'a spring operating againstmatic, and ot' a rod, cord, or chain and handle, to release said clamp.4

In consists, finally, in the peculiar construction and combination ofthe parts, as hereinafter set forth.

In the accompanying drawings, Figurel represents a vertical sectiontaken through the center of an extension lamp-fixture provided with myimprovement. Fig. 2 represents a detail view of the shoe and the innertube. Fig. 3 represents a detail view of the wedge, its spring, and apart of the rod attached thereto. Fig.4representsa detail perspectiveview of the incline case against which said wedge works in binding onsaid shoe.

The same letters indicate the same parts in the several figures.

A designates the bracket or hanger whereby the fixture is attached tothe ceiling of an apartment or hall; 13, the inner tube of said fixture,said inner tube being screwed into said hanger or attached thereto inany other convenient manner; 0, a pulley journaled in said hanger,around which the'suspending cord D passes, said cord beingcontinued downthrough I said tube to the lamp-support or harp E; and F, the outertube, which is screwed or otherwise conveniently attaehed to saidlamp-support and slides over said inner tube telescopically, in theusual manner.

nothing new, and their construction, combination, and arrangement may beconsiderably In the parts as thus far described there is varied withoutin the least affecting myinvention.

0n the upper end of outer tube, F, acase, G,

tube, B, and is arranged within the incline case G aforesaid.

I designates a sliding wedge which is forced upward by a spring, J,between shoe H and the inclined face or part 9 of case G. A rod,

.K, extends down from said wedge within the tube F, and is providedbelow the same with is screwed, which is hollow, and provided on ahandle, L, whereby said wedge can be withdrawn at will from between saidparts H and g. The shoe H is movable; but the top ofcasc Gr prevents itfrom being forced upward out of said case, and a shoulder, t, on theinner face of wedge I extends under said shoe to preventitifrom droppingdown out of place. The bottom of case G has an opening, g, to allow thedownward motion of said wedge when drawn by rod K. The lower bearing-ofspring J is against a lug, M,which is attached to or formed on the innertube, B, and is therefore stationary. As shown in the drawings, theinner face of the wedge and the outer face of the shoe arecorrespondinglyinclined. This construction makes the clamping actionmore reliable; but it is not strictly necessary, as the devices willwork very well when the contiguous faces are vertical. Of course a solidrod may be used instead of the inner tube, and a cord or chain may be.substituted for the rod K, attached to the wedge. Said rod may operateby pushing instead of pulling, the wedge being reversed and the springbeing arranged aboveit. In that case the incline gis of course invertedalso.

The operation isobvious, SpringJnormally holds the outer tube clamped totheinnerone by reason of its action against the wedge I. which it forcesbetween incline g and shoe H, thus preventing further descentof thelamp. 1 When the clamp is loosened, by pulling (or'when the parts areinverted by pushing) rod K the weight of the lamp and its attachmentswill draw down the outer tube in the usual manner. When said rod isreleased the clamping operation is automatically resumed.

All of the clamping devices described are exterior to the inner tube, B,and as the case G is easily detachable from the outer tube they mayreadily be inspected, removed, and cleaned or mended. They areexceedingly I simple and cheap in construction. They may be put togetherby inexpensive workmen oflittle special training, and noconsiderableamount of machine-work is required.

By using a suitable catch for rod K the spring J might be dispensedwith; but then the clamping action would not be automatic.

The case G constitutes in efiect a detachable extension of outer tube,F. Theinclined plane 9 within said case or extension is not absolutelyindispensable, provided the'outer faceot" the shoe H and the inner faceof wedge I be properly inclined to insure clamping action.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is

1. In combination with the inner tube or rod and the outer tube of anextension lamp-fixture, an automatic clamping device arranged outside ofsaid inner tube but within a case or extension of said outer tube,substantially as set forth.

2. In combination with the inner tube or rod and the outer tube of anextension lamp-fixture, a clamping device arranged outside of said innertube and within a detachable case or extension of said outertube,'substantially as set forth.

3. In combination with the inner tube or rod and the outer tube of anextension lam p-fixture, a shoe which bears against said inner tube, awedge operating against the back of said shoe, an external case orextension of the 5. In combination with the inner tube or rod and theouter tube of an extension lamp fixture, a shoe bearingagainst saidinner tube, a wedge operating against said shoe, an inclined plane whichis in 'contact with the outer face of said wedge, a spring which forcessaid wedge between said inclined plane and said shoe, and a rod wherebysaid wedge is withdrawn to release the outer tube from the inner one,substantially as set forth.

6. Wedge I, provided with shoulder i, in combination with shoe H. springJ, incline case G. and the outer and inner tubes of an extensionlamp-fixture, said shoe being held in position by said shoulder and thetop of said case, substantially as set forth.

7. A wedge, I, inclined on both faces, in combination with a shoe, H,inclined on its outer face, a case, G, having an inclined inner face,and a spring which forces said wedge between said inclined faces, saidshoe being arranged to bear against the inner tube or rod of anextension lamp-fixture, and said case being attached to the outer tubethereof, substantially as set forth.

8. The telescoped outer and inner tubes of an extension'lamp-fixture, incombination with a case detachably secured on the top of said outertube, and a wedge-spring and clampingshoe loose within said case andoperating, as set forth, said clamping devices being easily accessibleand removable when said case is taken off from said outer tube, as setforth.

In testimony whereof I affix my signature in presence of two Witnesses.

Witnesses:

RALPH A. PALMER, JOSEPH H. BECKETT.

DEXTER W. PARKER.

